1. The act of discriminating, distinguishing, or noting and marking differences. "To make an anxious discrimination between the miracle absolute and providential." Trench.2. The state of being discriminated, distinguished, or set apart. Sir J. Reynolds.3. (Railroads) The arbitrary imposition of unequal tariffs for substantially the same service. "A difference in rates, not based upon any corresponding difference in cost, constitutes a case of discrimination." A. T. Hadley.4. The quality of being discriminating; faculty of nicely distinguishing; acute discernment; as, to show great discrimination in the choice of means.5. That which discriminates; mark of distinction.